A wide variety of display devices have been designed and manufactured for use in merchandising shelved products to consumers. One of the major problems associated with storing and displaying shelved products for sale to customers and, in particular, shelved products requiring refrigeration in display coolers and other types of cold vaults, is the inefficient use of available shelf space and the inability of a merchant to provide a constant, attractive arrangement of shelved products which are readily visible and easily accessible to the customer at the front portion of the shelf. Equally important has been the problem of overcoming the poor utilization of available shelf space in a manner that is both most efficient and at the same time cost effective.
Various product shelving displays have been designed to alleviate such problems, but all such devices suffer from certain disadvantages and shortcomings including being relatively large, bulky, awkward, expensive, and difficult, if not impossible, to use on shelf space presently available in supermarkets and other retail outlets, including the shelf space available in conventional refrigerated display coolers. Furthermore, none of the known devices and methods for storing and merchandising shelved products are as simple structurally as the subject constructions and none utilize as efficient and effective means for both improving the slidability and availability of products positioned thereon and providing an adjustable unit easily adapted to accommodate a wide variety of conventional shelving. In this regard, the known devices capable of width and depth adjustments require a plurality of separate units to provide a single product merchandising display device. An example of such a device is disclosed in U.S. Pat. No. 4,364,481 which requires at least three separate elements each of which is specially constructed so that respective portions may be broken away to adjust both the depth and width thereof, the separate elements interlocking with one another to provide product troughs of various widths. Also, U.S. Pat. No. 4,593,823 discloses a gravity feed type system wherein only the side portions of the individual units are removable. U.S. Pat. No. 4,593,823 also discloses a two-tier system which utilizes means for achieving the two-tier arrangement which are substantially different from the means of the subject invention, namely, a different bracket design as well as a plurality of alternate bracket receiving means which must be used for attaching each individual bracket to the system. The shelving units of the subject invention as well as the means for arranging said units in a two-tier system is clearly distinguishable over the above known prior art.